Gynaecological or reproductive tract infections generally refer to three different types of infection which affect the reproductive tract. Endogenous infections include bacterial vaginosis and candidosis, which result from an overgrowth of organisms which are normally present in the vagina. The endogenous infections represent the most common form of lower gynaecological tract infections (LGTIs) worldwide, and they can be easily treated. However, they commonly reappear, which is a major medical problem. Iatrogenic infections represent a second group which occur when the infectious agent (a bacterium or other micro-organism) is introduced into the reproductive tract through various routes such as menstrual regulation, induced abortion, IUD insertion or during parturition. Finally, sexually transmitted infections (STIs) are caused by microorganisms such as viruses, bacteria, or parasitic microorganisms that are transmitted through sexual activity with an infected partner. Among the STIs there are several serious diseases such as HIV, chlamydia trachomatis, condyloma accuminata, syphilis and Neisseria gonorrhea. STIs can affect both men and women, but a transmission from mothers to children during pregnancy and childbirth may also occur.
Bacterial vaginosis (BV) is the most frequent endogenous infection and also the most common medical condition of the female genital tract. BV is linked to increased complications in pregnancy, and may be involved in the pathogenesis of pelvic inflammatory disease and women's risk of acquiring HIV. Still many questions remain about its aetiology, which complicates the management of recurrent infections.
BV is an overgrowth of anaerobic bacteria and a lack of normal Lactobacilli flora, which results in an imbalance of normal vaginal flora. During pregnancy BV is associated with poor perinatal outcome and a cause of preterm birth. Identification and treatment of BV may reduce the risk of such consequences. A range of therapeutic options has been tested in order to manage or prevent recurrences of BV.
It is not yet known whether frequent episodes of BV are the result of re-infection or relapse. The association of BV with sexual behaviour suggests that BV is sexually transmitted and that additional episodes may be due to re-infection. However, evidence do not support the theory of sexual transmission and re-infection and several studies evaluating risk factors for repeated episodes of BV suggest it is due to relapse. Women developing early recurrence tend to complain of abnormal discharge at the end of therapy. Moreover, asymptomatic women who consider themselves cured after treatment, continued to have abnormal vaginal flora. Furthermore, the more severe the abnormality the earlier is usually the recurrence.
The value of bacteriotherapy, using harmless bacteria to displace pathogenic organisms remain unresolved.
Psychosexual symptoms with lack of libido and anxiety about infection may be reported by some women as a consequence of recurrent episodes of bacterial vaginosis and associated malodour. However, concurrent treatment of the male partner does not reduce the rate of BV relapse. However, condom use with male sexual partners may help to reduce the risk of relapse of bacterial vaginosis. Hormonal contraception use does not increase the incidence of bacterial vaginosis, while women with an intrauterine contraceptive device or system in situ may have an increased risk of BV.
Vaginal Discharge
Vaginal discharge is a common presenting symptom, which may be physiological or pathological. While BV remains one of the most common diagnoses in women attending genitourinary medicine clinics, vulvovaginal candidiasis is another common infective cause of vaginal discharge that affects about 75% of women at some time during their reproductive life. Approximately 50% of cases of bacterial vaginosis are asymptomatic and the true prevalence of this condition in the community is about 10-30%. Lactobacilli colonising the vaginal epithelium may have a role in defence against infection. Normal vaginal flora (lactobacilli) maintains the vaginal pH between 3.8 and 4.4. The quality and quantity of vaginal discharge may be altered in the same woman over time. There is a wide variation in vaginal discharge and each woman has her own sense of normality and what is acceptable or excessive.
The main problem of the pathogenic vaginal discharge is the malodour. This odour has the characteristics of a foul fishy smell which is characteristic for bacterial vaginosis and caused by amines, mainly trimethylamine. Other clinical manifestations may be excessive discharge and a sense of unfreshness.
The present invention is a further development of the invention disclosed in WO 2008/119518 published on 9 Oct. 2008. In WO 2008/119518 oligomers of lactic acid and their therapeutic and prophylactic use are described. However, the formulations described therein suffered from problems envisaged during initial clinical studies such as too early discharge etc. and, accordingly, there is still a need for developing compositions that are user-friendly and remain on the administration site for a period of time to that allow administration only once or twice weekly.